diff options
Diffstat (limited to 'fs/notify/fanotify/fanotify_user.c')
-rw-r--r-- | fs/notify/fanotify/fanotify_user.c | 243 |
1 files changed, 131 insertions, 112 deletions
diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c index 3568c8a8b138..e44cb6427df3 100644 --- a/fs/notify/fanotify/fanotify_user.c +++ b/fs/notify/fanotify/fanotify_user.c @@ -13,10 +13,12 @@ #include <linux/slab.h> #include <linux/types.h> #include <linux/uaccess.h> +#include <linux/compat.h> #include <asm/ioctls.h> #include "../../mount.h" +#include "../fdinfo.h" #define FANOTIFY_DEFAULT_MAX_EVENTS 16384 #define FANOTIFY_DEFAULT_MAX_MARKS 8192 @@ -58,11 +60,11 @@ static struct fsnotify_event *get_one_event(struct fsnotify_group *group, return fsnotify_remove_notify_event(group); } -static int create_fd(struct fsnotify_group *group, struct fsnotify_event *event) +static int create_fd(struct fsnotify_group *group, + struct fsnotify_event *event, + struct file **file) { int client_fd; - struct dentry *dentry; - struct vfsmount *mnt; struct file *new_file; pr_debug("%s: group=%p event=%p\n", __func__, group, event); @@ -81,12 +83,10 @@ static int create_fd(struct fsnotify_group *group, struct fsnotify_event *event) * we need a new file handle for the userspace program so it can read even if it was * originally opened O_WRONLY. */ - dentry = dget(event->path.dentry); - mnt = mntget(event->path.mnt); /* it's possible this event was an overflow event. in that case dentry and mnt * are NULL; That's fine, just don't call dentry open */ - if (dentry && mnt) - new_file = dentry_open(dentry, mnt, + if (event->path.dentry && event->path.mnt) + new_file = dentry_open(&event->path, group->fanotify_data.f_flags | FMODE_NONOTIFY, current_cred()); else @@ -102,7 +102,7 @@ static int create_fd(struct fsnotify_group *group, struct fsnotify_event *event) put_unused_fd(client_fd); client_fd = PTR_ERR(new_file); } else { - fd_install(client_fd, new_file); + *file = new_file; } return client_fd; @@ -110,22 +110,25 @@ static int create_fd(struct fsnotify_group *group, struct fsnotify_event *event) static int fill_event_metadata(struct fsnotify_group *group, struct fanotify_event_metadata *metadata, - struct fsnotify_event *event) + struct fsnotify_event *event, + struct file **file) { int ret = 0; pr_debug("%s: group=%p metadata=%p event=%p\n", __func__, group, metadata, event); + *file = NULL; metadata->event_len = FAN_EVENT_METADATA_LEN; metadata->metadata_len = FAN_EVENT_METADATA_LEN; metadata->vers = FANOTIFY_METADATA_VERSION; + metadata->reserved = 0; metadata->mask = event->mask & FAN_ALL_OUTGOING_EVENTS; metadata->pid = pid_vnr(event->tgid); if (unlikely(event->mask & FAN_Q_OVERFLOW)) metadata->fd = FAN_NOFD; else { - metadata->fd = create_fd(group, event); + metadata->fd = create_fd(group, event, file); if (metadata->fd < 0) ret = metadata->fd; } @@ -224,25 +227,6 @@ static int prepare_for_access_response(struct fsnotify_group *group, return 0; } -static void remove_access_response(struct fsnotify_group *group, - struct fsnotify_event *event, - __s32 fd) -{ - struct fanotify_response_event *re; - - if (!(event->mask & FAN_ALL_PERM_EVENTS)) - return; - - re = dequeue_re(group, fd); - if (!re) - return; - - BUG_ON(re->event != event); - - kmem_cache_free(fanotify_response_event_cache, re); - - return; -} #else static int prepare_for_access_response(struct fsnotify_group *group, struct fsnotify_event *event, @@ -251,12 +235,6 @@ static int prepare_for_access_response(struct fsnotify_group *group, return 0; } -static void remove_access_response(struct fsnotify_group *group, - struct fsnotify_event *event, - __s32 fd) -{ - return; -} #endif static ssize_t copy_event_to_user(struct fsnotify_group *group, @@ -264,31 +242,34 @@ static ssize_t copy_event_to_user(struct fsnotify_group *group, char __user *buf) { struct fanotify_event_metadata fanotify_event_metadata; + struct file *f; int fd, ret; pr_debug("%s: group=%p event=%p\n", __func__, group, event); - ret = fill_event_metadata(group, &fanotify_event_metadata, event); + ret = fill_event_metadata(group, &fanotify_event_metadata, event, &f); if (ret < 0) goto out; fd = fanotify_event_metadata.fd; - ret = prepare_for_access_response(group, event, fd); - if (ret) - goto out_close_fd; - ret = -EFAULT; if (copy_to_user(buf, &fanotify_event_metadata, fanotify_event_metadata.event_len)) - goto out_kill_access_response; + goto out_close_fd; + + ret = prepare_for_access_response(group, event, fd); + if (ret) + goto out_close_fd; + if (fd != FAN_NOFD) + fd_install(fd, f); return fanotify_event_metadata.event_len; -out_kill_access_response: - remove_access_response(group, event, fd); out_close_fd: - if (fd != FAN_NOFD) - sys_close(fd); + if (fd != FAN_NOFD) { + put_unused_fd(fd); + fput(f); + } out: #ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS if (event->mask & FAN_ALL_PERM_EVENTS) { @@ -418,8 +399,9 @@ static int fanotify_release(struct inode *ignored, struct file *file) wake_up(&group->fanotify_data.access_waitq); #endif + /* matches the fanotify_init->fsnotify_alloc_group */ - fsnotify_put_group(group); + fsnotify_destroy_group(group); return 0; } @@ -450,6 +432,7 @@ static long fanotify_ioctl(struct file *file, unsigned int cmd, unsigned long ar } static const struct file_operations fanotify_fops = { + .show_fdinfo = fanotify_show_fdinfo, .poll = fanotify_poll, .read = fanotify_read, .write = fanotify_write, @@ -474,24 +457,22 @@ static int fanotify_find_path(int dfd, const char __user *filename, dfd, filename, flags); if (filename == NULL) { - struct file *file; - int fput_needed; + struct fd f = fdget(dfd); ret = -EBADF; - file = fget_light(dfd, &fput_needed); - if (!file) + if (!f.file) goto out; ret = -ENOTDIR; if ((flags & FAN_MARK_ONLYDIR) && - !(S_ISDIR(file->f_path.dentry->d_inode->i_mode))) { - fput_light(file, fput_needed); + !(S_ISDIR(file_inode(f.file)->i_mode))) { + fdput(f); goto out; } - *path = file->f_path; + *path = f.file->f_path; path_get(path); - fput_light(file, fput_needed); + fdput(f); } else { unsigned int lookup_flags = 0; @@ -515,7 +496,8 @@ out: static __u32 fanotify_mark_remove_from_mask(struct fsnotify_mark *fsn_mark, __u32 mask, - unsigned int flags) + unsigned int flags, + int *destroy) { __u32 oldmask; @@ -529,8 +511,7 @@ static __u32 fanotify_mark_remove_from_mask(struct fsnotify_mark *fsn_mark, } spin_unlock(&fsn_mark->lock); - if (!(oldmask & ~mask)) - fsnotify_destroy_mark(fsn_mark); + *destroy = !(oldmask & ~mask); return mask & oldmask; } @@ -541,12 +522,21 @@ static int fanotify_remove_vfsmount_mark(struct fsnotify_group *group, { struct fsnotify_mark *fsn_mark = NULL; __u32 removed; + int destroy_mark; + mutex_lock(&group->mark_mutex); fsn_mark = fsnotify_find_vfsmount_mark(group, mnt); - if (!fsn_mark) + if (!fsn_mark) { + mutex_unlock(&group->mark_mutex); return -ENOENT; + } + + removed = fanotify_mark_remove_from_mask(fsn_mark, mask, flags, + &destroy_mark); + if (destroy_mark) + fsnotify_destroy_mark_locked(fsn_mark, group); + mutex_unlock(&group->mark_mutex); - removed = fanotify_mark_remove_from_mask(fsn_mark, mask, flags); fsnotify_put_mark(fsn_mark); if (removed & real_mount(mnt)->mnt_fsnotify_mask) fsnotify_recalc_vfsmount_mask(mnt); @@ -560,12 +550,21 @@ static int fanotify_remove_inode_mark(struct fsnotify_group *group, { struct fsnotify_mark *fsn_mark = NULL; __u32 removed; + int destroy_mark; + mutex_lock(&group->mark_mutex); fsn_mark = fsnotify_find_inode_mark(group, inode); - if (!fsn_mark) + if (!fsn_mark) { + mutex_unlock(&group->mark_mutex); return -ENOENT; + } + + removed = fanotify_mark_remove_from_mask(fsn_mark, mask, flags, + &destroy_mark); + if (destroy_mark) + fsnotify_destroy_mark_locked(fsn_mark, group); + mutex_unlock(&group->mark_mutex); - removed = fanotify_mark_remove_from_mask(fsn_mark, mask, flags); /* matches the fsnotify_find_inode_mark() */ fsnotify_put_mark(fsn_mark); if (removed & inode->i_fsnotify_mask) @@ -601,35 +600,55 @@ static __u32 fanotify_mark_add_to_mask(struct fsnotify_mark *fsn_mark, return mask & ~oldmask; } +static struct fsnotify_mark *fanotify_add_new_mark(struct fsnotify_group *group, + struct inode *inode, + struct vfsmount *mnt) +{ + struct fsnotify_mark *mark; + int ret; + + if (atomic_read(&group->num_marks) > group->fanotify_data.max_marks) + return ERR_PTR(-ENOSPC); + + mark = kmem_cache_alloc(fanotify_mark_cache, GFP_KERNEL); + if (!mark) + return ERR_PTR(-ENOMEM); + + fsnotify_init_mark(mark, fanotify_free_mark); + ret = fsnotify_add_mark_locked(mark, group, inode, mnt, 0); + if (ret) { + fsnotify_put_mark(mark); + return ERR_PTR(ret); + } + + return mark; +} + + static int fanotify_add_vfsmount_mark(struct fsnotify_group *group, struct vfsmount *mnt, __u32 mask, unsigned int flags) { struct fsnotify_mark *fsn_mark; __u32 added; - int ret = 0; + mutex_lock(&group->mark_mutex); fsn_mark = fsnotify_find_vfsmount_mark(group, mnt); if (!fsn_mark) { - if (atomic_read(&group->num_marks) > group->fanotify_data.max_marks) - return -ENOSPC; - - fsn_mark = kmem_cache_alloc(fanotify_mark_cache, GFP_KERNEL); - if (!fsn_mark) - return -ENOMEM; - - fsnotify_init_mark(fsn_mark, fanotify_free_mark); - ret = fsnotify_add_mark(fsn_mark, group, NULL, mnt, 0); - if (ret) - goto err; + fsn_mark = fanotify_add_new_mark(group, NULL, mnt); + if (IS_ERR(fsn_mark)) { + mutex_unlock(&group->mark_mutex); + return PTR_ERR(fsn_mark); + } } added = fanotify_mark_add_to_mask(fsn_mark, mask, flags); + mutex_unlock(&group->mark_mutex); if (added & ~real_mount(mnt)->mnt_fsnotify_mask) fsnotify_recalc_vfsmount_mask(mnt); -err: + fsnotify_put_mark(fsn_mark); - return ret; + return 0; } static int fanotify_add_inode_mark(struct fsnotify_group *group, @@ -638,7 +657,6 @@ static int fanotify_add_inode_mark(struct fsnotify_group *group, { struct fsnotify_mark *fsn_mark; __u32 added; - int ret = 0; pr_debug("%s: group=%p inode=%p\n", __func__, group, inode); @@ -652,27 +670,23 @@ static int fanotify_add_inode_mark(struct fsnotify_group *group, (atomic_read(&inode->i_writecount) > 0)) return 0; + mutex_lock(&group->mark_mutex); fsn_mark = fsnotify_find_inode_mark(group, inode); if (!fsn_mark) { - if (atomic_read(&group->num_marks) > group->fanotify_data.max_marks) - return -ENOSPC; - - fsn_mark = kmem_cache_alloc(fanotify_mark_cache, GFP_KERNEL); - if (!fsn_mark) - return -ENOMEM; - - fsnotify_init_mark(fsn_mark, fanotify_free_mark); - ret = fsnotify_add_mark(fsn_mark, group, inode, NULL, 0); - if (ret) - goto err; + fsn_mark = fanotify_add_new_mark(group, inode, NULL); + if (IS_ERR(fsn_mark)) { + mutex_unlock(&group->mark_mutex); + return PTR_ERR(fsn_mark); + } } added = fanotify_mark_add_to_mask(fsn_mark, mask, flags); + mutex_unlock(&group->mark_mutex); if (added & ~inode->i_fsnotify_mask) fsnotify_recalc_inode_mask(inode); -err: + fsnotify_put_mark(fsn_mark); - return ret; + return 0; } /* fanotify syscalls */ @@ -732,13 +746,13 @@ SYSCALL_DEFINE2(fanotify_init, unsigned int, flags, unsigned int, event_f_flags) break; default: fd = -EINVAL; - goto out_put_group; + goto out_destroy_group; } if (flags & FAN_UNLIMITED_QUEUE) { fd = -EPERM; if (!capable(CAP_SYS_ADMIN)) - goto out_put_group; + goto out_destroy_group; group->max_events = UINT_MAX; } else { group->max_events = FANOTIFY_DEFAULT_MAX_EVENTS; @@ -747,7 +761,7 @@ SYSCALL_DEFINE2(fanotify_init, unsigned int, flags, unsigned int, event_f_flags) if (flags & FAN_UNLIMITED_MARKS) { fd = -EPERM; if (!capable(CAP_SYS_ADMIN)) - goto out_put_group; + goto out_destroy_group; group->fanotify_data.max_marks = UINT_MAX; } else { group->fanotify_data.max_marks = FANOTIFY_DEFAULT_MAX_MARKS; @@ -755,25 +769,25 @@ SYSCALL_DEFINE2(fanotify_init, unsigned int, flags, unsigned int, event_f_flags) fd = anon_inode_getfd("[fanotify]", &fanotify_fops, group, f_flags); if (fd < 0) - goto out_put_group; + goto out_destroy_group; return fd; -out_put_group: - fsnotify_put_group(group); +out_destroy_group: + fsnotify_destroy_group(group); return fd; } -SYSCALL_DEFINE(fanotify_mark)(int fanotify_fd, unsigned int flags, - __u64 mask, int dfd, - const char __user * pathname) +SYSCALL_DEFINE5(fanotify_mark, int, fanotify_fd, unsigned int, flags, + __u64, mask, int, dfd, + const char __user *, pathname) { struct inode *inode = NULL; struct vfsmount *mnt = NULL; struct fsnotify_group *group; - struct file *filp; + struct fd f; struct path path; - int ret, fput_needed; + int ret; pr_debug("%s: fanotify_fd=%d flags=%x dfd=%d pathname=%p mask=%llx\n", __func__, fanotify_fd, flags, dfd, pathname, mask); @@ -807,15 +821,15 @@ SYSCALL_DEFINE(fanotify_mark)(int fanotify_fd, unsigned int flags, #endif return -EINVAL; - filp = fget_light(fanotify_fd, &fput_needed); - if (unlikely(!filp)) + f = fdget(fanotify_fd); + if (unlikely(!f.file)) return -EBADF; /* verify that this is indeed an fanotify instance */ ret = -EINVAL; - if (unlikely(filp->f_op != &fanotify_fops)) + if (unlikely(f.file->f_op != &fanotify_fops)) goto fput_and_out; - group = filp->private_data; + group = f.file->private_data; /* * group->priority == FS_PRIO_0 == FAN_CLASS_NOTIF. These are not @@ -862,19 +876,24 @@ SYSCALL_DEFINE(fanotify_mark)(int fanotify_fd, unsigned int flags, path_put(&path); fput_and_out: - fput_light(filp, fput_needed); + fdput(f); return ret; } -#ifdef CONFIG_HAVE_SYSCALL_WRAPPERS -asmlinkage long SyS_fanotify_mark(long fanotify_fd, long flags, __u64 mask, - long dfd, long pathname) +#ifdef CONFIG_COMPAT +COMPAT_SYSCALL_DEFINE6(fanotify_mark, + int, fanotify_fd, unsigned int, flags, + __u32, mask0, __u32, mask1, int, dfd, + const char __user *, pathname) { - return SYSC_fanotify_mark((int) fanotify_fd, (unsigned int) flags, - mask, (int) dfd, - (const char __user *) pathname); + return sys_fanotify_mark(fanotify_fd, flags, +#ifdef __BIG_ENDIAN + ((__u64)mask1 << 32) | mask0, +#else + ((__u64)mask0 << 32) | mask1, +#endif + dfd, pathname); } -SYSCALL_ALIAS(sys_fanotify_mark, SyS_fanotify_mark); #endif /* |